Week 1 Non Associative learning & Classical Conditioning PDF

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Week 1 lecture pt 1 and 2...

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[1]: Historical context of the study of learning - During the 20th century, two major approaches to studying learning arose (i.e behavioural & cognitive) - Both approaches share commonalities Note: Cognitive psychologists are interested in understanding complex abilities - Tend to focus on mechanistic basis of behaviour - How information is processed to produce an outcome or response Note: Behavioural psychologists are interested in broad learning principles - Emphasis on outward, external observable behaviours and environment stimuli - Mechanisms behind behaviour are thought to be of little relevance only outcome/response matters

Learning: The Grassroots Defintion: Learning is the acquisition of knowledge or skills through experience - Learning cannot be observed directly, instead revealed by change in behaviour and the brain - These changes allow us to adapt to our environment Note: Learning can be direct or indirect Direct: Learning through your own experience (i.e very effective) Indirect: Learning through observing others behaviour (i.e particularly important for children/infants) - Observational learning is important for animals too

Why include studies of animals? - We are animals Note: Continuity of species e.g We share main characteristics with animals such as striking anatomical similarities during gestation - Simpler versions - They are a blank slate as we can control and know an animal's entire experience of the world

Why is understanding learning so important? - Learning helps us understand and adapt to challenges e.g Learn where to find food and avoid predators - Explains likes and dislikes Note: Learning principles are often used to shape behaviour - Increase desirable behaviours (e.g regular exercise) - Decrease unwanted behaviours (e.g anxiety) Note: The basic principles of learning are harnessed in… - Advertising, educational settings, clinical and even medical treatment settings

Advertisers use learning to shape our behaviour: Advertisers use basic principles of learning to shape our consumer behaviour - Shapes what we like and don’t like - What products we buy Note: Associative learning is key to advertising - Associative their product with things we like and or admire

Advertising: - Advertising often capitalises on existing positive responses to stimuli, associating their product with it Note: Can fail dissmaly if these positive responses are not within their target audience - Advertising can also capitalise on existing negative responses to stimuli (e.g smoking) - Having bad experience with certain alcohol such as throwing up can lead to conditioned taste aversion

Learning: Clinical Psychology and beyond - Sometimes animals fail to learn or they might learn the wrong thing - This can contribute to mental health issues in humans Note: Mental health is the number 1 health problem in developed countries - More years lost to disability - Greater costs than all cancers combined - Learning is involved in the origin and maintenance of some mental health disorders Note: Evidence that individuals with mental health problems learn about the world in a different way E.g Anxiety (i.e abnormal fear learning and maintenance) E.g Schizophrenia and Autism (i.e abnormal habituation) E.g Addiction (i.e Why vulnerable? Why overdose?) - Understanding basic principles of learning can help us improve treatment e.g Anxiety disorders, phobias, PTSD and controlled exposure therapy

[2] What is learning? Defintion: Learning is the aquisition of knowledge or skills through experience - Typically learning is revealed by a change in behavioural, physiological and or neural reactions/responses

Why is learning important? Learning allows animals to adapt to their environment Non-associative learning: - Notice important events and learn to ignore events that occur without consequence Associative learning: - Learn what stimuli predict events and what behaviours are associated with certain consequences (i.e punishment/reward) in order to better predict or seek/avoid such consequences

Not all changes are a result of learning? - Behavioural, physiological and neural changes can occur in absence of learning entirely e.g Fatigue, illness and drugs Note: How can you tell if a behavioural change is not related to learning? 1: It is not a consequence of experience 2: It is temporary as learning is often long lasting and can ONLY be changed through experience

Associative vs Non-associative learning: Associative learning: Is learning process where new response becomes associated with particular S Note: This can occur via the creation of associations between

- Two stimuli (e.g A bell and food for Pavlov’s dogs) - A behaviour and its consequence (e.g holding out its paw for a shake and getting a treat) Non-associative learning: Learning that results in a change in the frequency/amplitude of a behaviour in response to repeated exposures of a particular stimulus - Increase in response (i.e sensitisation) - Decrease in the response (i.e habituation)

Types of non-associative learning: Habituation - Both people and animals notice novelty from birth - Thus, when something new happens we pay attention to it via showing an orienting response Orienting response: Is when you move/lean toward and attend to direction of the new stimulus/event Note: However, after repeated exposure to the stimulus we habituate Habituation: A progressive decrease in response amplitude or frequency as a consequence of repeated experience with a stimulus - Habitutation is stimulus specific - Habitutation is both short and long term and can last hours, days or even weeks - This typically occurs to a stimulus judged to be of no or little importance to us

Short vs Long term habitutation: Leaton (1976): Rat startle responding - Tones once per day produced lasting, long-term habituation - Tones every 3 seconds produced deeper, BUT shorter habituation Note: Shows spontaneous recovery in the diagram - Short interstimulus interval (ISI) leads to good short-term habituation, but long ISI leads to good long-term habituation IMPORTANT: There are 2 types of processes/forms of habituation (i.e long and short)

Examples of habiutation: Long term habituation example: - A novel sound initially makes an eating cat panic, BUT if the sound is repeated daily, the cat habituates and eats without a reaction e.g People often habituate to the smell of their own dog in their house or car, or to their own perfume - This is stimulus-specific so people do notice the pet smell in someone elses house

Example of habitutation: Brain response Mutschler et al (2010): - Measured humans response times to classical piano music - Valence and arousal ratings dropped with time as did the response time in left and right amygdala

Habituation is NOT sensory adaptation: - Sensory adaptation is tendency of sensory receptors to fatigue and stop responding to an unchanging stimulus as said receptors change their sensitivity to stimulus

Note: This is a physical bottom-up process

How can I tell if its habituation vs sensory adaptation: - With sensory adaptation you cannot capture the initial stimulus e.g Jumping into a pool of cold water for the first time, you do the same thing 15 minutes later and you can’t recreate the same feeling - With habituation you can capture the initial stimulus e.g If there is an annoying sound you can tune it out, however, you can hear that sound if you redirect your attention back to where the sound is coming from

Failures of habituation in clinical groups: - Seeing emotional faces activates the amygdala Breiter et al (1996): Reduced levels of habituation were shown in individuals with… - Anxiety disorders - ASD - Schizophrenia Note: Dishabituation provides critical insight into how atypical indivudals react to world around them

Habitutation and Dishabituation: Dishabituation: Recovery in responsiveness to an already habituated stimulus - Habituation to fridge noise means we no longer hear the noisy fridge; however, the addition of novel stimuli reorients us to the dishabituated stimulus meaning we now hear noisy fridge again - Another example is that the siren would alert pedestrians to the traffic

Why does the first bite always taste the best? - First bite always tastes best due to habituation - Tend to overeat at parties due to different foods acting as disinhbituators meaning slower habituation - We tend to have room for dessert because habituation is stimulus specific Note: Sensory specific satiety, also plays a role in these effects

Types of non-associative learning: Sensitisation Sensitisation: - An increase in response amplitude or frequency as a consequence of repeated exposure to a stimulus - Sensitisation is typically NOT stimulus specific - Often occurs when anticipating an important stimulus so that we are prepared for important cues Note: Sensitisation and habituation are commonly studied using the startle and orienting response

Examples of Sensitisation: (i.e also in the brain): Nervous pen clicking example: - Sensitisation would occur when the pen clicking elicited increased orienting or attentional responses in contrast with habituation which would elicit decreased response rate Buzzing mosquito example:

- While we can fall asleep to the sound of a fridge a buzzing mosquito can keep us awake all night Boileau et al (2006): - Brain response to amphetamines (i.e dopamine release in striatum)

Types of non-associative learning: Desensitisation Desensitisation: A decrease in response amplitude or frequency back down to baseline as a consequence of repeated experience with a stimulus Note: Habituation/sensitisation are normal responses to repeated events BUT when does one occur over the other?

Infant Study: Habituation and Sensitisation Experimental procedure: - Infants were shown either visually complex or simple patterns 8 times for 10 seconds each Simple: 4x4 pattern & Complex: 12x12 pattern Measured: Time spent looking at the stimulus - Habituation and sensitisation affected responding on the same behaviour Note: Results to right show fixation time for trials - Looking time steadily decreased over trials as infant habituated to simpler 4x4 stimulus - Looking time increased to complex 12x12 stimulus (sensitisation) before it decreased (habituation)

Habituation and Sensitisation: - Results show that attention elicited by a novel stimulus changes with familiarity Note: The nature of change depends on the nature of the stimulus Simple stimulus > Progressive habituation Complex stimulus > Sensitisation > Habituation

Infant Study: Dishabituation - Visual fixation became habituated to a 4x4 chequerboard stimulus presented over 8 trials - After trial 8, a tone was presented as a disinhabituating stimulus along with the chequerboard pattern causing recovery of visual fixation to the pattern

When Habitutation or Sensitisation: Intensity of the stimulus: Low intensity stimuli typically elicit habituation while high intensity stimuli typically elicit sensitisiation whereas intermediate stimuli elicit a period of sensitisation followed by habituation Note: The evolutionary significance of the stimulus can override the intensity e.g Essential for mother to not habituate the babys cry (i.e rather adaptive to sensitise them) e.g Mosquitoes carry diseases and their bites are unpleasant

Dual Process theory of Habituation and Sensitisation: - Sensitisation is thought to be a companion process to habituation that opposes the effects of habituation in many, BUT not all situations

- Sensitisation may occur NOT only during the first few presentations of a stimulus, but also at the introduction of an unexpected stimulus from another modality Note: The underlying processes of habituation and sensitisation can co-occur together - The observable behaviour is the summation of these two processes - The habituation effect is observed when the habituation process is greater than the sensitisation process and vice versa Key assumption: Respond to repeated presentations of a non-signal stimulus reflect the operation of two separate processes, habituation and sensitisation - Habituation produces a stimulus specific decline in responding to repeated stimulation, and grows stronger as the number of repetitions increases - The state-mediated sensitisation process produces increases in responsiveness on early trials, which decay spontaneously over time - These two processes are though to sum to determine overt responding, with sensitisation serving as a “gain control” on the final response pathway

Summary: Non-associative learning Habituation: - Repeated exposure to stimuli can result in a decrease in the elicited response - The weaker the stimuli the more rapid the habituation - The response decrement shows stimulus specificity Sensitisation: - Repeated exposure to stimuli can result in an increase in the elicited response - The stronger the stimuli the more rapid the sensitisation - The response increase generalizes to other stimuli in the domain

[3]: What is classical conditioning? - The procedure of repeatedly pairing an initial neutral stimulus and an unconditioned stimulus that reliably elicits an uncondition response Note: After conditioning the neutral stimulus becomes established as a conditioned stimulus with the capacity to elicit a conditioned response that usually resembles the unconditioned response

Key elements of classical conditioning: - Neutral stimulus (NS) - Unconditioned stimulus (US) - Unconditionfed response (UR) - Conditioned stimulus (CS) - Conditioned response (CR)

Classical conditioning of Dwight: - What was the NS? Reboot sound - What is the US? Being offered a mint - What is the UR? Putting hand out

- What is the CS? Reboot sound - What is the CR? Putting hand out

Classical conditioning of Rachel Berry & Timing of condition and unconditioned stimulus: : - What was the NS? Glass of water - What is the US? Sad event - What is the UR? Feeling sad - What is the CS? Glass of water - What is the CR? Feeling sad

Examples of Classical conditioning: - Condtioning of hunger US: Taste and smell of food UR: Internal physiological changes that prepare us to digest and metabolise food such as secretion of saliva, gastric juices, insulin etc... IMPORTANT: Insulin lowers blood sugar which stimulates our hunger levels CS: Kitchen, fridge, sight of food, packet of chips > hunger > CR - Separation anxiety in dogs Note: Classical conditioning imbues previously neutral sound of jingling keys the ability to elicit separation anxiety

Classical conditioning overview & Acquisition of learning : Learning follows a negatively accelerating curve…. - Acquisition - Non-linear - Asymptote

Types of unconditioned stimuli: Appetitive US: Automatically elicits approach responses, such as eating, drinking, caressing, etc… Aversive US: Such as noise, bitter taste, electric shock etc.. and elicit avoidance and escape responses Note: Appetitive classical conditioning is slower and requires greater numbers of acquisition trials - BUT, aversive classical conditioning is established one, two or three trails depending on the intensity of the aversive US

Appetitive Conditioning: - Appetitive conditioning utilises a positive reinforcing stimulus such as food, water or sex - Animals conditioned with an appetitive stimulus will often approach and contact the stimulus signalling its availability (e.g a bell or light) Note: How can a cold metal bowl be so comforting to a rescue dog though?

Aversive Conditioning: - Aversive conditioning is accomplished with a mildly painful or unpleasant US

- In typical fear conditioning experiments, the tone or light CS is paired with an aversive US such as a mild electric shock Note: Fear conditioning engenders various autonomic and behavioural response, is a rapid form of learning and only requires a single CS & US paired under the right conditions - The two process model of aversive conditioning posits that emotional CRs (e.g fear) emerge first, followed by more specialised and adaptive CRs (e.g running) Note: Different CRs can be triggered the same US

What form does the conditioned response take? Stimulus substitution theory: - Pavlov believed that the CS became a substitute for the US Note: Innate US-UR reflex pathway - CS substitutes for the US in evoking the same response - CR and UR produced by same neural region - Food > Salivation - CS > Salivation Note: If this is true, the CR should always be the same as the UR

Evidence FOR stimulus substitution hypothesis: Jenkins & Moore (1973): Signtracking in pigeons study - One group had CS (light) > US (grain) - Pigeons tried to “eat” the lit key (i.e open beak and closed eyes) when they pecked - Another group had CS (light) > US (water) - Pigeons tried to “drink” the lit key (i.e closed beak and open eyes) when they pecked Note: CR is sometimes directed at the CS - This demonstrates that the nature of the US determines the form of the CR

Sign-tracking and individual differences: - The sign-tracking CR is an involuntary Pavlovian response that is triggered automatically by the presentation of the CS and performed regardless of the intention of the subject - Sign-tracking CR performance is so poorly controlled that the subject is often unable to restrain the performance even at the cost of losing the reward US E.g Sign-tracking seen in raccoons Note: Some animals are sign-trackers and some are goal trackers - Sign trackers direct their behaviour at the CS (e.g light) even at the expense of the US (e.g reward) - Goal trackers behaviour is directed to the US Note: Both sign and goal trackers are learning that the CS predicts the food outcome, BUT only sign trackers ascribe incentive to the cue (i.e CS) - Rats who display sign tracking towards a CS predictive of food are more likely to develop compulsive cocaine self-administration

Sign-tracking and addiction in humans:

- Research from animals on sign tracking is applied to look at whether people who overeat/susceptible to addiction are overly sensitive to cues associated with food or alcohol - Conditioned stimuli that signal reward become motivational magnets that capture attention even when individuals are motivated to ignore them Note: Sign-tracking offers account of how impulsive and involuntary behaviour begins and is triggered by cues and why erosion of self control may go unnoticed

Evidence AGAINST stimulus substitution hypothesis: - Any study in which the elicited CR is different from the UR Note: This is often the case with aversive US e.g When a tone is paired with shock, rats will jump to the US (shock) BUT the CR is typically freezing - Freezing is a preperatory defense response

Alternative accounts: Preparatory response theory - Kimbles (1961, 1967) theory proposed that the CR is a response that serves to prepare the organism for the upcoming US e.g Following acquisition of CRs in eye-blink conditioning, the CR may actually prepare the person for the upcoming air-puff to the eye

Preparatory response example: Spotto game: Just the sight of a yellow car makes you cringe in anticipation of a punch to the arm

Alternative accounts: Compensatory response theory - In this model of classical conditioning, the compensatory after-effects to a US are what comes to be elicited by the CS Note: Based on the opponent process theory of motivation - Central goal is to maintain a state of homeostasis

Compensatory response model: Drug taking and compensatory response model: - Drug (US) > Rush (UR) - Withdrawal/compensatory resposne (UR) - If a CS (syringe) precedes the drug US, then the CR elicits withdrawal component (i.e builds tolerance)

Compensatory responses in the real world: Heroin overdose mystery: - Many heroin overdose victims die after self-administering an amount of opiate that should NOT ha...